Influence of mesh materials on the integrity of the vas deferens following Lichtenstein hernioplasty: an experimental model

A prospective randomized comparison of sexual function and semen analysis following laparoscopic totally extraperitoneal (TEP) and transabdominal pre-peritoneal (TAPP) inguinal hernia repair

BACKGROUND

With standardization of laparoscopic technique of groin hernia repair, the focus of surgical outcome has shifted to lesser studied parameters like sexual function and fertility.

METHODS

This prospective randomized study was conducted in a single surgical unit at a tertiary care hospital. A sample size of 144 was calculated with 72 in each group (Group 1 TEP and Group 2 TAPP). Primary outcomes measured included comparison of sexual function using BMFSI, qualitative semen analysis and ASA levels between patients undergoing TEP or TAPP repair. Semen analysis and ASA was measured pre-operatively and 3 months post-operatively.

RESULTS

A total of 145 patients were randomized into two groups, TAPP (73) and TEP (72) patients. Both the groups were comparable in terms of demographic profile and hernia characteristics with majority of the patients in both the groups having unilateral inguinal hernia (89.0% in TAPP group and 79.2% in TEP group). Both the groups showed statistically significant improvement in overall sexual function score (BMFSI) at 3 months; however, there was no inter group difference. Both the groups were also comparable in terms of ASA and qualitative semen analysis.

CONCLUSION

Both TEP and TAPP repair are comparable in terms of sexual function and effect on semen analysis. Laparoscopic repair improves the overall sexual functions in patients with groin hernia.

Could polypropylene mesh impair male reproductive organs? Experimental study with different methods of implantation

PURPOSE

To evaluate the vas deferens and testicles of rats submitted to bilateral inguinotomy and polypropylene (PP) mesh placement.

METHOD

Sixty Wistar rats were randomized into three groups: Control (inguinotomy only), mesh placement over the vas deferens (Mesh-DD) or under the spermatic funiculus (Mesh-SF). The following analyses were performed: vas deferens morphometry (lumen area and wall thickness), quantification of collagen fibers, spermatogenesis, apoptosis (cleaved caspase-3 and TUNEL) and cellular proliferation (Ki67). Quantitative gene expression (qPCR) for apoptosis and inflammatory cytokines were evaluated by RT-PCR.

RESULTS

In the apoptosis pathway, Mesh-DD showed one upregulated gene (Il10) and three downregulated genes (Fadd, Tnfrsf1b and Xiap). In Mesh-SF, 17 genes were downregulated. In the inflammation pathway (Mesh-DD), one gene was upregulated (Il1r1), and one gene was downregulated (Ccl12). In Mesh-SF, three genes were upregulated (Il1r1, Tnfsf13b and Csf1), and two were downregulated (Ccl12 and Csf2). PP mesh placement preserved spermatogenesis and did not alter the vas deferens or the testicle. In the ductus deferens, there was reduced luminal area (30 days), increased wall thickness (90 days), and increased type III collagen and cell proliferation (30 and 90 days) (p < 0.05). In the testicle, cell proliferation was greater in the Mesh-DD (p < 0.05).

CONCLUSIONS

PP mesh, whether or not in direct contact with spermatic funicular structures, induces changes that were not sufficient to cause damage to the evaluated organs.

Does a bilateral polypropylene mesh alter the duct deferens morphology, testicular size and testosterone levels? Experimental study in rats

Purpose

To evaluate the effect of a PP mesh on duct deferens morphology, testicular size and testosterone levels.

Methods

Forty adult male rats were distributed into groups: 1) no surgery; 2) inguinotomy; 3) mesh placed on the duct deferens; and 4) mesh placed on the spermatic funiculus. After 90 postoperative days, the inguinal region was resected, and blood samples were collected for the measurement of serum testosterone (pg/dl). The ducts deferens were sectioned in three axial sections according to the relationship with the mesh — cranial, medial and caudal. The wall thickness and duct deferens lumen area were measured.

Results

The morphology of the duct deferens was preserved in all groups. The mesh placement did not alter this morphology in any of the analyzed segments. Surgery, with or without mesh placement, did not alter the morphology, wall thickness or lumen area (p>0.05). In all operated groups, serum testosterone levels were similar (p>0.05) but there was a decrease in testicle size (p<0.05).

Conclusion

Surgery, with or without mesh placement, did not alter the morphology of the duct deferens and, although this treatment resulted in testicular size reduction, it did not affect serum testosterone levels.

Does the use of hernia mesh in surgical inguinal hernia repairs cause male infertility? A systematic review and descriptive analysis

Objective

The aim of this study was to systematically review the available clinical trials examining male infertility after inguinal hernias were repaired using mesh procedures.

Methods

The Cochrane Library, PubMed, Embase, Web of Science, and Chinese Biomedical Medicine Database were investigated. The Jada score was used to evaluate the quality of the studies, “Oxford Centre for Evidence-based Medicine-Levels of Evidence” was used to assess the level of the trials, and descriptive analysis was used to evaluate the studies.

Results

Twenty nine related trials with a total of 36,552 patients were investigated, including seven randomized controlled trials (RCTs) with 616 patients and 10 clinical trials (1230 patients) with mesh or non-mesh repairs. The Jada score showed that there were six high quality RCTs and one low quality RCT. Levels of evidence determined from the Oxford Centre for Evidence-based Medicine further demonstrated that those six high quality RCTs also had high levels of evidence. It was found that serum testosterone, LH, and FSH levels declined in the laparoscopic group compared to the open group; however, the testicular volume only slightly increased without statistical significance. Testicular and sexual functions remained unchanged after both laparoscopic transabdominal preperitoneal hernia repair (TAPP) and totally extra-peritoneal repair (TEP). We also compared the different meshes used post-surgeries. VyproII/Timesh lightweight mesh had a diminished effect on sperm motility compared to Marlex heavyweight mesh after a one-year follow-up, but there was no effect after 3 years. Additionally, various open hernia repair procedures (Lichtenstein, mesh plug method, posterior pre-peritoneal mesh repair, and anterior tension-free repair) did not cause infertility.

Conclusions

This systematic review suggests that hernia repair with mesh either in an open or a laparoscopic procedure has no significant effect on male fertility.

An experience with mesh versus darn repair in inguinal hernias

Background & Objective:

The inguinal hernia accounts for 50 percent in old age males. A Lichtenstein type of operation has now become the method of choice in most developed countries but in the developing world traditional simple suture repair is still in common practice in resource limited hospitals due to the scarcity and expensive nature of the commercial prosthetic mesh. Our objective was to compare the rates of complications in Lichtenstein repair to tension free Darn repair.

Methods:

Ninety two male patients from 20-60 years of age reported for direct or indirect inguinal hernia with open Mesh/Lichtenstein or darn repair in emergency or electively from January 2014 to December 2015 were enrolled in this prospective randomized control trial (RCT). The primary end point was to compare the surgical site infection, length of hospital stay and hernia recurrence with different techniques.

Results:

The hospital stay was higher in patients who had Lichtenstein repair, Superficial surgical site infections in cohort A (6.5%) and cohort B (4.36%)were noted. Complications of recurrence in Group-A were (1.5%) as compared to Group-B which had a recurrence of 6.52%.

Conclusion:

Lichtenstein is more promising in comparison to Darn repair in terms of recurrence in inguinal hernia.

In vivo response to polypropylene following implantation in animal models: a review of biocompatibility

INTRODUCTION AND HYPOTHESIS

Polypropylene is a material that is commonly used to treat pelvic floor conditions such as pelvic organ prolapse (POP) and stress urinary incontinence (SUI). Owing to the nature of complications experienced by some patients implanted with either incontinence or prolapse meshes, the biocompatibility of polypropylene has recently been questioned. This literature review considers the in vivo response to polypropylene following implantation in animal models. The specific areas explored in this review are material selection, impact of anatomical location, and the structure, weight and size of polypropylene mesh types.

METHODS

All relevant abstracts from original articles investigating the host response of mesh in vivo were reviewed. Papers were obtained and categorised into various mesh material types: polypropylene, polypropylene composites, and other synthetic and biologically derived mesh.

RESULTS

Polypropylene mesh fared well in comparison with other material types in terms of host response. It was found that a lightweight, large-pore mesh is the most appropriate structure.

CONCLUSION

The evidence reviewed shows that polypropylene evokes a less inflammatory or similar host response when compared with other materials used in mesh devices.

[Azoospermia and a history of inguinal hernia repair in adult]

BACKGROUND

Inguinal hernia repair is one of the most performed surgeries in the world. It is recognized that any surgery of the pelvic floor may represent a risk factor of male infertility.

METHOD

Retrospective study of patients with azoospermia and a history of adult inguinal hernia repair surgery and referred to our center between January 1990 and January 2011 for infertility.

RESULTS

Among 69 azoospermia patients with history of adult inguinal hernia repair surgery, 60 patients underwent surgical extraction of sperm that was successful in 75% (45/60). Positive extraction rate decreases in the subgroup of patients with risk factors for infertility (61.4%) as well as in the group with bilateral inguinal hernia (67.9%). There was no statistically significant difference in the positive rate of sperm retrieval according to surgical technique or according to the use of polypropylene mesh (P>0.05).

CONCLUSION

The obstruction of the vas deferens due to an inguinal hernia repair was a potential iatrogenic cause of male infertility that was rare and underestimated. The influence of using a polypropylene mesh was not clearly demonstrated. The management of these patients is based on prevention in order to identify patients with risk factors of infertility in order to propose a presurgery cryopreservation of sperm.

LEVEL OF EVIDENCE

5.

Lower reoperation rates with the use of fibrin sealant versus tacks for mesh fixation

BACKGROUND

Groin hernia repair may be associated with long-term complications such as chronic pain, believed to result from damage to regional nerves by tissue penetrating mesh fixation. Studies have shown that mesh fixation with fibrin sealant reduces the risk of these long-term complications, but data on recurrence and reoperation rates after the use of fibrin sealant compared with tacks are not available. This study aimed to determine whether fibrin sealant is a safe and feasible alternative to tacks with regard to reoperation rates after laparoscopic groin hernia repair.

METHODS

The current study compared reoperation rates after laparoscopic groin hernia repair between fibrin sealant and tacks used for mesh fixation. The study used data collected prospectively from The National Danish Hernia Database and analyzed 8,314 laparoscopic groin hernia repairs for reoperation rates. Mesh fixation was performed with fibrin sealant (n = 784) or tacks (n = 7,530).

RESULTS

The findings showed a significantly lower reoperation rate for the fibrin sealant than for the tacks (0.89 vs 2.94 %, p = 0.031). The median follow-up period was 17 months (range, 0-44 months) for the fibrin sealant group and 21 months (range, 0-44 months) for the tacks group.

CONCLUSIONS

Fibrin sealant was superior to tacks for mesh fixation in laparoscopic groin hernia repair with regard to reoperation rates. The study could not differentiate between different hernia defect sizes, and future studies should therefore explore whether the superior effect of fibrin sealant applies for all hernia types and sizes.

Obstructive azoospermia: reconstructive techniques and results

Obstructive azoospermia is a common cause of male infertility and can result from infection, congenital anomalies, or iatrogenic injury. Microsurgical vasal reconstruction is a suitable treatment for many cases of obstructive azoospermia, although some couples will require sperm retrieval paired with in-vitro fertilization. The various causes of obstructive azoospermia and recommended treatments will be examined. Microsurgical vasovasostomy and vasoepididymostomy will be discussed in detail. The postoperative patency and pregnancy rates for surgical reconstruction of obstructive azoospermia and the impact of etiology, obstructive interval, sperm granuloma, age, and previous reconstruction on patency and pregnancy will be reviewed.

Comparison of long-term biocompability of PVDF and PP meshes

BACKGROUND

Abdominal hernia repair is the most frequently performed operation in surgery. Mesh repair in hernia surgery has become an integral component. Although meshes made of PVDF are already in clinical use, so far no data of long-term biocompability are available.

METHODS

In this study a PVDF mesh was compared to a polypropylene mesh with regard to its long-term biocompatibility. A total of 28 rats were randomized to two groups. Mesh material was implanted subcutaneously; animals were euthanized seven days and six months postoperatively. The quantity of inflammatory tissue response was characterized by measuring the diameter of the foreign body granuloma. Furthermore quality of cellular immune response (T-lymphocytes, macrophages, and neutrophils), and inflammation (COX-2) was analyzed by immunohistochemistry. Furthermore the collagen type I/III ratio was determined.

RESULTS

Macrophages, T-lymphocytes, neutrophiles, and COX-2 declined significantly up to six months postoperatively in comparison to day 7 for both PVDF and PP meshes, and in both groups the collagen ratio increased significantly in the course of time. PVDF meshes showed a foreign body granuloma size significantly reduced compared to PP (7 days: 20 ± 2 μm vs. 27 ± 2 μm; 6 months 15 ± 2 μm vs. 22 ± 3 μm; p < .001). However no significant differences were found analyzing cellular response six months postoperatively.

CONCLUSIONS

Our current data suggest that even in the long-term course after six months and despite a higher effective surface of the PVDF samples it showed a smaller foreign body granuloma than with PP whereas the cellular response was similar.

Testicular functions, chronic groin pain, and quality of life after laparoscopic and open mesh repair of inguinal hernia: a prospective randomized controlled trial

BACKGROUND

Laparoscopic inguinal hernia repair is still not the gold standard for patients with inguinal hernia. The aim of this study was to compare testicular dysfunction, incidence and factors influencing chronic groin pain, and quality of life after laparoscopic and open mesh repair.

METHODS

One hundred twenty patients were studied in a prospective randomized trial. One hundred seventeen patients completed the required follow-up, 60 following laparoscopic repair and 57 following open repair. Testicular functions were assessed by testicular volume, blood flow, and hormones, and quality of life was assessed with Short Form 36 version 2 preoperatively and postoperatively at 3 months. Pain was assessed at different time intervals preoperatively and postoperatively.

RESULTS

Preoperative profiles of both groups were well matched. A significant decrease in testicular volume (p = 0.01) and less improvement in blood flow (p = 0.048) was seen after open repair. There was also a significant reduction in serum testosterone level (p = 0.02) with a significant increase in FSH and LH level (p < 0.001); however, there was no testicular atrophy. Incidence and severity of chronic groin pain were significantly less after laparoscopic repair during normal and strenuous activities, though they were similar to those after open repair during rest after 3 months postoperatively. Age, preoperative pain, pain at 1 week, and open repair were found to be independent risk factors for chronic pain on multivariate analysis. Quality of life was significantly better postoperatively in terms of physical functions, role physical, bodily pain, and general health after laparoscopic repair.

CONCLUSION

Laparoscopic repair seems favorable in terms of better preservation of testicular functions, lower incidence of acute and chronic groin pain, and significant improvement in quality of life when compared to open repair. Younger age, preoperative pain, pain after 1 week postoperatively, and open mesh repair were found to be significant risk factors for chronic groin pain.

Influence of the Elasticity Module of Synthetic and Natural Polymeric Tissue Substitutes on the Mobility of the Diaphragm and Healing Process in a Rabbit Model

Mesh implants are frequently used in congenital diaphragmatic hernia. This experimental study aimed to examine the influence of different materials on the diaphragmatic movement over time as well as their mechanical qualities after 4 months. Ultrapro®, Surgisis®, and Proceed ® were implanted onto a diaphragmatic defect in growing rabbits. Diaphragmatic mobility was determined at three time points. At 4 months, defect shrinkage and mechanical properties were measured. The break strength decreased for Ultrapro® and Surgisis®, but did not change relevantly for Proceed®. Ultrapro® (32.46 N/cm) and Proceed® (31.75 N/cm) showed a four-fold higher resistance to tearing than Surgisis® (8.31 N/cm). The elasticity of Ultrapro® showed no significant difference compared to Surgisis® ( p = 0.75). Proceed®, on the other hand, was more than twice as elastic as Ultrapro® or Surgisis ® ( p = 0.015). Ultrapro® had a higher spring rate (6.48 N/mm) compared to Surgisis® (3.82 N/mm) or Proceed ® (5.23 N/mm). Observing the standardized movement rates of the diaphragm for each mesh group over time the only statistical differences were seen for the Proceed® group. On account of its material qualities Ultrapro® was found to be the most suitable mesh material for demanding locations in our model.

Damage to the spermatic cord by the Lichtenstein and TAPP procedures in a pig model

BACKGROUND

Mesh implantation is regarded as the standard treatment of inguinal hernias. Obstructive azoospermia induced by mesh implantation is a rare but serious complication. Whether different operative techniques or mesh materials used have an effect on the integrity of the testicle and spermatic cord remains unclear.

MATERIALS

In 12 minipigs a bilateral inguinal hernia repair, either open or laparoscopic, was performed using a standard small-pore polypropylene (PP) or large-pore polyvinyliden fluoride (PVDF) mesh. Next to measurement of the testicular size, thermography of the groin and testicle as a parameter for perfusion was performed preoperatively and at a follow-up at 6 months. Obstructions of the vas deferens were estimated radiographically. Testicular function (Johnson score) and mesh integration (granuloma size, apoptotic cells) were analyzed histologically.

RESULTS

Mean testicular size did not change significantly in follow-up compared to preoperative values. Technique and mesh material used failed to have a significant influence. Thermography of the groin following the Lichtenstein technique had significantly higher values at follow-up regardless of the mesh used. This could not been shown for laparoscopic treatment. Thermographic measurements at the testicle showed a significantly increased temperature in all groups compared to preoperative measurements. Only the Lichtenstein PP group showed significantly decreased values in testicular function. Quantity and quality of obstructions seen at vasography were most detectable in the Lichtenstein PP group. There was significantly decreased granuloma formation following PVDF mesh implantation compared to the PP mesh group regardless of the technique used.

CONCLUSIONS

Both the technique and the mesh material have an impact on integrity of spermatic cord and testicular function. According to the results of this study, the laparoscopic TAPP procedure using a large-pore PVDF mesh has the least effect compared to preoperative values.

Litigation following groin hernia repair in England

PURPOSE

Since 1995, litigation following surgical procedures has cost the National Health Service (NHS) over 1.3 billion GBP (Great British Pounds)/2.1 billion USD (United States Dollars)/1.4 billion Euros. Despite it being the most commonly undertaken general surgical operation, no study has examined clinical negligence claims in England following groin hernia repairs.

METHODS

Data from the NHS Litigation Authority of all claims made from 1995 to 2009 was obtained and interrogated.

RESULTS

In total, 398 claims were made. Of these, 209 cases had been settled, of which 144 (46.6%) were in favour of the claimant to a cost of 7.35 million GBP/12 million USD/7.93 million Euros. Testicular injury and chronic pain featured in 40% of all claims. Visceral injuries and injuries requiring corrective procedures were the only predictors of a successful claim (P = 0.015 and P = 0.002, respectively). Claims associated with visceral and vascular injuries were more likely to occur in laparoscopic than in open repairs. Sexual dysfunction and chronic pain resulted in the highest average payouts of 85,467 GBP/140,565 USD/92,177 Euros and 81,288 GBP/133,693 USD/87,674 Euros, respectively.

CONCLUSION

Patients should be fully informed of the incidence of testicular injury and chronic pain during the consent process. Approaches minimising visceral and vascular injury particularly in laparoscopic repair should be adopted to reduce litigation and improve patient care.

Impact of mesh positioning on foreign body reaction and collagenous ingrowth in a rabbit model of open incisional hernia repair

BACKGROUND

Incisional hernia remains as one of the most common surgical complications. Different mesh techniques are used in 75-80% of hernia repair. The aim of this study was to evaluate the dependence of mesh positioning and the type of mesh implanted on foreign body reaction and collagenous ingrowth.

MATERIALS AND METHODS

In 24 male Chinchilla rabbits, an incisional hernia repair was performed with mesh reinforcement either by sublay (n = 12) or by onlay technique (n = 12). In each group, two different types of mesh prosthesis were investigated: polypropylene (PP, Prolene) and polypropylene-polyglecaprone 25 composite (PP-PG, UltraPro). On postoperative day 60, the inflammatory and connective tissue formation was characterised by measuring the diameter of inner cellular infiltrate and outer fibrous capsule of the foreign body granuloma, and by verifying the collagen type I/III ratio. Furthermore, the expression of matrix metalloproteinase-2 (MMP-2) was analysed.

RESULTS

Microscopic investigation of the mesh/host-tissue interface showed typical formation of foreign body granuloma. The diameters of the inner part of the foreign body granuloma representing the amount of inflammatory cell infiltrate were significantly increased in the PP mesh compared to the PP-PG mesh, both in the sublay group (PP 13.1 +/- 1.21 microm vs. PP-PG 11.7 +/- 0.34 microm; P = 0.026) and in the onlay group (PP 13.1 +/- 1.24 microm vs. PP-PG 11.2 +/- 0.55 microm; P = 0.009). The diameter of the fibrous capsule as the outer ring of the granuloma was significantly increased when investigating the PP mesh in sublay position (29.5 +/- 1.12 microm) compared to the PP mesh in onlay position (27.9 +/- 0.73 microm) (P = 0.026). Investigating the quality of perifilamentary collagen deposition expressed as collagen type I/III ratio, the sublay group showed significantly elevated values compared to the onlay group (PP sublay 3.1 +/- 0.18 vs. PP onlay 2.4 +/- 0.41; P = 0.004) (PP-PG sublay 3.5 +/- 0.34 vs. PP-PG onlay 2.6 +/- 0.13; P = 0.002). The analysis of MMP-2 expression revealed no significant differences.

CONCLUSION

The beneficial results of mesh reinforcement in the sublay technique might be due to a superior quality of postoperative connective tissue formation. Mesh incorporation, irrespective of positioning, is favourable in low-weight, large, porous mesh material represented by a reduced inflammatory part of the foreign body granuloma.